May 2007 doc IEEE 802 11 070792 r

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 Freedom to use 40 MHz at 5 GHz Date: 2007 -05 -16 Authors: Notice: This document has been prepared to assist IEEE 802. 11. It is offered as a basis for discussion and is not binding on the contributing individual(s) or organization(s). The material in this document is subject to change in form and content after further study. The contributor(s) reserve(s) the right to add, amend or withdraw material contained herein. Release: The contributor grants a free, irrevocable license to the IEEE to incorporate material contained in this contribution, and any modifications thereof, in the creation of an IEEE Standards publication; to copyright in the IEEE’s name any IEEE Standards publication even though it may include portions of this contribution; and at the IEEE’s sole discretion to permit others to reproduce in whole or in part the resulting IEEE Standards publication. The contributor also acknowledges and accepts that this contribution may be made public by IEEE 802. 11. Patent Policy and Procedures: The contributor is familiar with the IEEE 802 Patent Policy and Procedures <http: // ieee 802. org/guides/bylaws/sb-bylaws. pdf>, including the statement "IEEE standards may include the known use of patent(s), including patent applications, provided the IEEE receives assurance from the patent holder or applicant with respect to patents essential for compliance with both mandatory and optional portions of the standard. " Early disclosure to the Working Group of patent information that might be relevant to the standard is essential to reduce the possibility for delays in the development process and increase the likelihood that the draft publication will be approved for publication. Please notify the Chair stuart@ok -brit. com as early as possible, in written or electronic form, if patented technology (or technology under patent application) might be incorporated into a draft standard being developed within the IEEE 802. 11 Working Group. If you have questions, contact the IEEE Patent Committee Administrator at <patcom@ieee. org>. Submission 1 Tomoko Adachi, Toshiba Corporation et al.

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 Authors (Cont'd): Submission 2 Tomoko Adachi, Toshiba Corporation et al.

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 Abstract • This argues: – Importance of 40 MHz operation at 5 GHz for CE application – 20 M/40 M coexistence: 5 GHz vs. 2. 4 GHz – Freedom to use 40 MHz channel at 5 GHz in an appropriate environment Submission 3 Tomoko Adachi, Toshiba Corporation et al.

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 40 MHz at 5 GHz is Essential for CE Applications: Higher Throughput and Robustness • Typical requirements of CE application – Multiple compressed HDTV streamings (25 Mbps/stream or more). – Full coverage of home • Throughput and robustness is important to satisfy the requirements. • Therefore, lower MCS using 40 MHz would be chosen, especially for 5 GHz, due to higher propagation loss. Submission 4 Tomoko Adachi, Toshiba Corporation et al.

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 20 M/40 M Coexistence: 5 GHz is easier than 2. 4 GHz • At 2. 4 GHz – 5 MHz channel step is defined and, mainly 25 MHz separation is implemented – 802. 11 b as well as 802. 11 g must be considered as the legacy system for coexistence. • At 5 GHz: – 20 MHz channel separation is defined and implemented – Coexistence with only 802. 11 a legacy systems • This makes coexistence with 11 a at 5 GHz easier than with 11 b/g at 2. 4 GHz Submission 5 Tomoko Adachi, Toshiba Corporation et al.

May 2007 doc. : IEEE 802. 11 -07/0792 r 0 Conclusion • 40 MHz operation at 5 GHz is essential for CE applications. • 20 MHz/40 MHz coexistence at 5 GHz is easier than at 2. 4 GHz. • 11 n AP should have freedom to choose a 40 MHz channel with OBSS in the extension channel if: – There is no 40 MHz channel without OBSS in 5 GHz spectrum. – The traffic in the OBSS is not heavy. Submission 6 Tomoko Adachi, Toshiba Corporation et al.